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The understanding of how the neuron (the basic functional cell of the nervous system) works is
fundamental to all processes such as sensation, perception, memory, emotion, cognition, etc., in
health and in disease.

In this article, the second of a series on the fundamentals of the neuron, you will learn how inorganic
ions, the cell membrane and basic processes, such as diffusion and ion transport, generate one of
its basic and most important characteristics, the resting membrane potential.

The resting membrane potential is a stable electrical charge of approximately -65 to -70 milivolts of
the internal side (inside the cell) in relation to the external side. It is the basis of bioelectricity, that is,
the generation and use of electrical energy by excitable cells such as the neuron to perform its
functions of storage and transmission of information.

The last article of the series, in the next issue, will explain how neurons actively transmit information
by means of the action potential. The action potential is a sudden and reversible depolarization
(reversal of the membrane potential value) which propagates across the dendrites and axon of a
neuron.

1. Ions, Water and Membranes
2. Movement of Ions: Diffusion and Membranes
3. Movement of Ions: Electrical Charge
4. Resources on the Internet

Next issue: How Nerve Cells Work. Part II

About the Authors

Silvia Helena Cardoso, PhD. Psychobiologist, master and doctor in Sciences. Editor-in-chief of Brain & Mind. State University of Campinas, Brazil.

Renato M.E. Sabbatini, PhD. director of the Center for Biomedical Informatics and Chairman of Medical Informatics of the Medical School of the State University of Campinas, Campinas, Brazil.

André Malavazzi Designer